1. Field of the Invention
The present invention relates to a marine vessel steering apparatus and a marine vessel including the same. The marine vessel steering apparatus turns a rudder unit by an actuator controlled according to the operation of a steering wheel. The rudder unit is arranged to be mounted pivotally on a hull. One example of the rudder unit is an outboard motor with a built-in propulsion unit.
2. Description of Related Art
U.S. Patent Application Publication No. 2007/0089661 A1 discloses a prior art outboard motor steering control system. This system includes an actuator for turning an outboard motor with respect to a hull. The actuator is controlled electrically based on a value detected by a wheel angle sensor.
In the prior art above, the rotation angle of the steering wheel and the rudder angle of the outboard motor are detected when the internal-combustion engine included in the outboard motor starts. If there is a phase difference between the rotation angle of the steering wheel and the rudder angle of the outboard motor, phase difference elimination control is performed. The phase difference elimination control is for eliminating the phase difference between the rotation angle of the steering wheel and the rudder angle of the outboard motor. In this case, the outboard motor automatically moves, which may be unexpected by an operator. Hence, the prior art is arranged to inform the operator of the direction and/or magnitude of the phase difference when performing the phase difference elimination control.